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All of Johnston's schools were closed Tuesday due to threats made against students and staff, according to Johnston police and school officials.

Late Monday night, individual students and parents received anonymous messages, threatening their safety, officials said. Police are investigating.

According to a post on the district's website, "Around 8 p.m. on the evening of October 2, individual students and parents within our school district received anonymous messages, threatening the safety and security of our students. In an effort of caution, we will be canceling school for all students and district staff on Tuesday, October 3."

Early Tuesday morning, Johnston city spokeswoman Janet Wilwerding confirmed that the threats were sent via text message from the phone number 818-275-6848.

A Johnston mother received these text messages the night of Oct. 2, 2017. The Johnston school district closed all schools Oct. 3, as multiple parents reported receiving threatening messages and police were investigating. Explicit language has been edited out of this image.(Photo: Breana Schwitters / Special to the Register)

Johnston police are asking anyone who may have received one of these messages to take a screenshot of the message and email it to johnstonpolice77@gmail.com, along with a phone number to contact for further questions.

If community members have questions, they can contact Johnston police at 515-278-2345, Wilwerding said. Anyone with additional information on the threats is also asked to call police.

Breana Schwitters, of Johnston, said she was one of the parents who received these text messages, regarding her 4-year-old son.

"It's pretty scary. My son just started going to school," Schwitters told The Des Moines Register on Tuesday morning.

A Johnston mother received these text messages the night of Oct. 2, 2017. The Johnston school district closed all schools Oct. 3, as multiple parents reported receiving threatening messages and police were investigating. Explicit language has been edited out of this image.(Photo: Breana Schwitters / Special to the Register)

Schwitters said she received the text messages at about 7:30 p.m. while she was watching TV with her son and her son's father.

One of the messages included an address that had her house number, but the wrong street, she said. Others said, "Your child is still so innocent," and "Don't have anyone look outside."

At first, Schwitters said, she thought someone was playing a joke on her.

"But when it started talking about how my child is so innocent and don't look outside, I started freaking out," she said.

She soon called the police. When a Johnston police officer arrived, he said they had received more than 20 calls regarding similar messages, Schwitters said.

Police officials have not publicly confirmed how many people reportedly received these messages.

Schwitters said she was happy about the school district's decision to cancel classes.

"My child will not be going to school until they figure out who it is," she said.

Laura Sprague, communications director for the Johnston school district, told the Register Monday night that the decision to cancel school wasn't easy, "But my gosh, we can't take any chances."

School officials say that they are working with the Johnston Police Department "to track down the validity of the message and its source."

Johnston Police Chief Dennis McDaniel confirmed Monday night that his department is investigating the threats, saying, "We're still deep into this and working with all of our available resources."

The Johnston school district has about 7,200 students and about 1,000 employees.

Johnston police and city officials scheduled a press conference for 10:30 a.m. Tuesday, to provide more information.

Wilwerding added in an email Tuesday morning that false reports have been circulating on social media about a Johnston student being detained in relation to this incident. Police wanted to publicly clarify that those reports are false, she said.

Johnston schools Superintendent Corey Lunn sent the following message Monday night to all students' families and staff members:

Good evening, Johnston Parents and Staff, Tonight, individual students and parents within our school district received anonymous messages, threatening the safety and security of our students. These messages started arriving around 8 p.m. and have continued throughout the night. In an effort of caution, we will be canceling school for all students and district staff tomorrow, Tuesday, October 3. All district buildings will be closed and there is no KTC program.

School district officials are working closely with the Johnston Police Department to track down the validity of the message and its source.

We understand this may inconvenience parents and caretakers and we regret sending this message at a late hour. However, the safety of our students - your children - is the foremost reasoning behind this action.

As we receive information from the Johnston Police Department, we will keep you updated. If you have information related to these threats, please contact the Johnston Police Department at 515-278-2345.

This has been one of the toughest decisions I've had to make; please know I take the safety of all our students and staff seriously and feel this is the best choice for our district and school community.